package reflect;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

/**
 * 反射性能分析
 */
public class Test06 {
    //普通方式
    public static void test01() {
        User user = new User();
        long startTime = System.currentTimeMillis();

        //10e次
        for (int i = 0; i < 1000000000; i++) {
            user.getName();
        }

        long endTime = System.currentTimeMillis();

        System.out.println("普通执行10e次需要："+(endTime-startTime)+"ms");

    }
    //反射方式
    public static void test02() throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
        User user = new User();
        Class c1 = user.getClass();

        Method getName = c1.getDeclaredMethod("getName", null);
        long startTime = System.currentTimeMillis();

        //10e次
        for (int i = 0; i < 1000000000; i++) {
            getName.invoke(user,null);
        }

        long endTime = System.currentTimeMillis();

        System.out.println("反射执行10e次需要："+(endTime-startTime)+"ms");

    }


    //反射方式。关闭检测

    public static void test03() throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
        User user = new User();
        Class c1 = user.getClass();

        Method getName = c1.getDeclaredMethod("getName", null);
        getName.setAccessible(true);
        long startTime = System.currentTimeMillis();

        //10e次
        for (int i = 0; i < 1000000000; i++) {
            getName.invoke(user,null);
        }

        long endTime = System.currentTimeMillis();

        System.out.println("关闭检测后，执行10e次需要："+(endTime-startTime)+"ms");

    }

    public static void main(String[] args) throws InvocationTargetException, NoSuchMethodException, IllegalAccessException {
        test01();
        test02();
        test03();
    }
}
